FR3082265A1 - ROTATING SATELLITE HOLDER FOR A MECHANICAL REDUCER OF A TURBOMACHINE - Google Patents

Abstract

Rotating planet carrier for a mechanical reduction gear (10) of a turbomachine, this planet carrier comprising an annular row of tubular members (16, 50) for bearing supports (17) which are parallel to each other and to an axis of rotation (X) of the planet carrier, characterized in that each of the tubular members comprises oil circulation grooves (72) which are connected to oil conduits (58) and extending from the grooves to said external peripheral surface, these grooves being substantially rectilinear and parallel to each other as well as to an axis of revolution (Y) of an internal cylindrical surface (16b) of the corresponding tubular member, at least some of said grooves having a width or angular extent around said axis of revolution, which is greater than the diameter of the conduits connected to this groove, and at least some of said conduits being connected to the corresponding groove at one of the longitudinal edges x (72a) of this groove, namely that which is closest to said axis of rotation (X) of the planet carrier.

Description

ROTATING SATELLITE HOLDER FOR A MECHANICAL REDUCER OF A TURBOMACHINE

Field of the invention

The present invention relates to the field of speed reducers for a turbomachine in particular of an aircraft, and more specifically mechanical reducers whose planet carrier is rotating, that is to say mobile in rotation. The invention is particularly suitable, but not exclusively, for reducers whose satellites are mounted on roller bearings.

State of the art

The state of the art includes documents W0-A1-2010 / 092263, FR-A1 -2 987 416, FR-A1 -3 041 054 and W0-A1 -2014/037659.

The role of a mechanical reducer is to modify the speed ratio and the torque between the input axis and the output axis of a mechanism.

The new generations of turbofans with double flow, in particular those having a high rate of dilution, comprise a mechanical reducer to drive the shaft of a blower (also called "fan"). Usually, the purpose of the reduction gear is to transform the so-called fast rotation speed of the shaft of a power turbine into a slower rotation speed for the shaft driving the fan.

Such a reducer comprises a central pinion, called a sun gear, a crown and pinions called satellites, which are engaged between the sun and the crown. The satellites are held by a chassis called satellite carriers. The sun, the crown and the planet carrier are planetary because their axes of revolution coincide with the longitudinal axis X of the turbomachine. The satellites each have a different axis of revolution distributed equally over the same operating diameter around the axis of the planets. These axes are parallel to the longitudinal axis X.

There are several reducer architectures. In the state of the art of double-flow turbomachines, the reducers are of the planetary or planetary type. In other similar applications, so-called differential or "compound" architectures exist.

o on a planetary gearbox, the planet carrier is fixed and the crown constitutes the output shaft of the device which rotates in the opposite direction to the sun.

o on an epicyclic reducer, the crown is fixed and the satellite carriers constitute the output shaft of the device which rotates in the same direction as the sun.

o on a differential reducer, no element is fixed in rotation. The crown rotates in the opposite direction to the solar and the satellite carriers.

The reducers can be composed of one or more meshing stages. This meshing is ensured in different ways such as by contact, by friction or even by magnetic field.

There are several types of contact meshing such as straight or chevron teeth.

The operation of the reducers requires a particularly high oil flow rate to ensure the lubrication and cooling of its mechanical elements.

However, this type of reducer has drawbacks linked to its lubrication.

In the current technique, a satellite is generally guided in rotation by a bearing which extends around a tubular support of the planet carrier, this tubular support comprising an internal oil-receiving chamber and substantially radial through holes of oil passage from the internal chamber to the bearing.

For an epicyclic reducer, it is preferable to guide the satellites by plain bearings, but it has already been proposed to replace these bearings by roller bearings. The distribution of lubricating oil in such bearings is, however, even more complex since the rollers on the one hand and the bearing cages on the other must be lubricated effectively. These difficulties are due to the centrifugation of the oil and are therefore due to the fact that the planet carrier is movable in rotation. In the absence of an effective oil distribution at the bearings, the oil flow is highest at the orifices furthest from the axis of rotation of the planet carrier and the lowest at the orifices closer, precisely where the need for lubrication is greatest because the bearing cage exerts significant pressure on the tracks of the inner ring.

The present invention provides an improvement to this technology which makes it possible to optimize the lubrication of a gearbox with rotating planet carrier for which the lubricating oil of the planet carrier is subjected in operation to large centrifugal fields.

Statement of the invention

According to a first aspect, the invention relates to an oil distribution device for a rotating planet carrier of a mechanical reduction gear of a turbomachine, characterized in that this device is configured to be integral, preferably coaxially, with a tubular member for supporting a bearing of the planet carrier, said device comprising an oil inlet and a row, preferably annular, of oil outlets opening onto an external surface intended to be surrounded at least in part by said organ, said device comprising at least two internal cavities connected in series by at least one calibrated orifice, one of these cavities, called receiving cavity, being connected to said oil inlet, and internal calibrated channels for conveying oil extending, preferably substantially radially, from said cavities to orifices in said external surface of the device to form said oil outlets.

In the present application, the term "annular row" means a distribution around a circumference. In the case of oil outlets, they are therefore distributed or distributed around a circumference. The circumference here extends over the external periphery of the device and is therefore centered on the axis of revolution of the device.

The invention thus provides a device dedicated to the distribution of oil in a tubular member of a mobile planet carrier of a reduction gear. This device can be in the form of a disc or include such a disc, which can be integrated into the body or attached to it. This device essentially comprises internal cavities, calibrated orifices for connecting the internal cavities to each other, and channels for connecting the cavities to oil outlet orifices located at the external periphery of the device.

The device is configured to be integral with the tubular member of the bearing support and has a shape allowing it to be mounted. It therefore does not necessarily have a perfectly circular peripheral contour for example. This device is advantageously removable.

In the present application, the term "calibrated" orifices and channels means orifices and channels whose passage section is predetermined as a function of a desired oil flow rate. This calibration takes into account the position of the orifices and channels with respect to the axis of rotation of the satellite carriers and therefore the centrifugal fields applied to the oil which circulates in these zones in operation.

In the present application, the term “tubular member of a satellite carrier” means the combination of a tubular support and an internal ring of a rolling bearing. The inner ring is mounted around the tubular support and can be formed in one piece with this support. Alternatively, the ring is attached and mounted on the tubular support.

The device according to the invention may include one or more of the following characteristics, taken in isolation from one another, or in combination with one another:

the device is configured to be attached and fixed, for example by shrinking, in said tubular member,

- the cavities are arranged along a line which passes substantially through the center of the device and preferably by a radius of the device,

- said receiving cavity is close to the periphery of the device and is intended to be the closest to an axis of rotation of the planet carrier when the device is mounted on the planet carrier,

said device comprises an internal bore in which are inserted and fixed, for example by shrinking, pellets which each include one of said calibrated orifices, said pellets delimiting between them said cavities,

said bore is stepped and comprises several sections of different diameter and preferably arranged from the section of smaller diameter to the section of larger diameter, the latter opening out at the periphery of the device,

said device comprises a circular base, one face of which is machined and an annular cover attached to said base, on the side of its machined face, this face being machined to define said cavities and said channels between the base and the cover,

- said base comprises at its periphery an annular row of lunulas connected to said oil outlets,

- one of said cavities is machined throughout the thickness of said base to also form said oil inlet,

- said base and said cover each comprise an annular row of holes for fixing fixing screws,

- said base or said cover is integral with a gripping member to facilitate assembly and disassembly of the device,

- said base and / or said cover comprises an indexing means for its angular positioning in the tubular support,

- each of said cavities has a generally cylindrical shape whose axis of revolution is oriented perpendicular to the plane of the device or located in the plane of the device,

- said oil inlet is closer to the external periphery of the device than to its center,

- said oil inlet is oriented in a direction perpendicular to the plane of the device,

the channels are positioned symmetrically with respect to a plane perpendicular to said device,

the diameters of the channels are chosen between 0.5 and 3mm, and preferably between 0.7 and 2mm, and

- The diameters of the calibrated orifices are chosen between 0.5 and 7mm, and preferably between 0.7 and 5mm.

The present invention also relates to a rotating planet carrier for a mechanical reduction gear of a turbomachine, this planet carrier comprising an annular row of tubular bearing support members which are parallel to each other and to an axis of rotation of the planet carrier , cylindrical tracks and surfaces for guiding bearings and at least one cage of these bearings being defined at the periphery of each of the tubular members, and at least one device as described above being integral coaxially with each of these members tubular.

The planet carrier according to the invention may include one or more of the following characteristics, taken in isolation from one another, or in combination with each other:

each of said tubular members comprises a tubular support having an external cylindrical surface for mounting an internal bearing ring, and on which are formed oil circulation grooves which are in fluid communication with said oil outlets of the device, d on the one hand, and oil conduits formed in the internal ring, on the other hand, said grooves being substantially rectilinear and parallel to each other as well as to an axis of revolution of the cylindrical surface,

each of said tubular supports comprises through holes for fluid communication of said grooves with said oil outlets of the device,

each of said grooves is connected to several conduits, on the one hand, and by a single hole to a single oil outlet and to a single channel of said device, on the other hand,

at least some of said grooves have an angular width or extent around said axis of revolution, which is greater than the diameter of the holes and of the channel connected to this groove,

- The channel is connected to the corresponding groove at a first longitudinal edge of this groove, and the holes are connected to this groove at a second opposite longitudinal edge of this groove, and, for each groove, said first edge being further from said axis of rotation of the planet carrier than is said second edge.

The present invention also relates to an aircraft turbomachine, characterized in that it comprises a device or a planet carrier as described above.

According to a second aspect, the invention relates to a planet carrier rotating for a mechanical reduction gear of a turbomachine, this planet carrier comprising an annular row of tubular bearing support members, which are parallel to each other and to an axis of rotation of the satellite carriers, each of said tubular members comprising an external peripheral surface defining cylindrical tracks and surfaces for guiding bearings and at least one cage of these bearings, and an internal cylindrical surface delimiting an internal chamber configured to be supplied with oil in operation, oil passages extending between the internal cylindrical surface and the external peripheral surface for conveying the oil from said chamber to the bearings and to the cage, characterized in that each of the tubular members comprises oil circulation grooves which are connected to channels forming at least part of the said passages and extending from the grooves to said external peripheral surface, these grooves being substantially rectilinear and parallel to each other as well as to an axis of revolution of said internal cylindrical surface of the corresponding tubular member, at least some of said grooves having an angular width or extent around said axis of revolution, which is greater than the diameter of the conduits connected to this groove, and at least some of said conduits being connected to the corresponding groove at one of the longitudinal edges of this groove, namely that which is closest to said axis of rotation of the satellite carriers.

The invention relates here to a planet carrier, each tubular member of which comprises an oil circulation network which is designed to better distribute the oil between the different channels. In operation, due to the centrifugal fields, the oil is forced to accumulate mainly at the longitudinal edges of the grooves which are furthest from the axis of rotation of the planet carrier. The oil collects in the grooves and simultaneously feeds the conduits which are located at the opposite longitudinal edges. The oil flows which supply these different conduits are therefore substantially identical, which guarantees optimal lubrication of the cylindrical tracks of the members.

The planet carrier according to the invention may include one or more of the following characteristics, taken in isolation from one another, or in combination with each other:

- each of said tubular members comprises a tubular support and an internal ring of at least one rolling bearing, this internal ring being integrated into said support or attached and fixed around said support,

each of said tubular supports comprises an external cylindrical surface on which said internal ring is mounted, said passages comprising, on the one hand, said conduits which extend between said external peripheral surface defined by the ring and said grooves, and, on the other hand, through holes which extend between said internal cylindrical surface and said grooves, the grooves being formed between the tubular support and the ring,

- said grooves are formed on the external cylindrical surface of each tubular support,

- said holes are connected to the grooves at the level of the other of the longitudinal edges of these grooves, namely that which is furthest from said axis of rotation of the planet carrier,

- each of said grooves is connected to several conduits, on the one hand, and to a single hole, on the other hand,

- an oil distribution device is associated with each of said tubular members and comprises a device configured to be coaxially secured to the corresponding tubular member,

- Said device comprises an oil inlet and a row, preferably annular, of oil outlets opening onto an external surface intended to be surrounded at least in part by the member, said device comprising at least two internal cavities connected in series by at least one calibrated orifice, one of these cavities, called the receiving cavity, being connected to said oil inlet, and internal calibrated oil conveying channels extending, preferably substantially radially, from said cavities up to orifices in said external surface of the device to form said oil outlets which are in fluid communication with said grooves,

- Said device is configured to be attached and fixed, for example by shrinking, in said tubular member.

The present invention also relates to an aircraft turbomachine, characterized in that it comprises a planet carrier as described above.

Brief description of the figures

Other characteristics and advantages will emerge from the following description of a non-limiting embodiment of the invention with reference to the accompanying drawings in which:

FIG. 1 is a schematic view in axial section of an aircraft turbomachine,

FIG. 2 is a very schematic and simplified view of a planetary gear train in particular of a speed reducer,

FIG. 3 is a partial schematic view in axial section of a speed reducer with a rotating planet carrier,

FIG. 4 is a diagrammatic cutaway view in perspective of the reducer of FIG. 3,

FIG. 5 is a schematic cross-sectional view of a tubular member of a planetary gearbox carrier,

- Figure 6 is a schematic view in axial section of the tubular member of Figure 5;

FIG. 7 is a schematic cross-sectional view of a tubular member of a reduction gearbox carrier fitted with an oil distribution device according to the invention,

FIG. 8 is a partial schematic view in perspective of a cylindrical track for guiding a cage of a rolling bearing of the reducer,

- Figure 9 is a schematic view in axial section of an alternative embodiment of the device according to the invention;

FIG. 10 is a schematic view in cross section along the line A-A of FIG. 9, the device being mounted in a tubular member of planet carrier,

FIGS. 11 and 12 are schematic cross-sectional views of the tubular member of FIG. 9, without and with the device,

- Figure 13 is a schematic view in axial section of a tubular planet carrier, equipped with an alternative embodiment of the device according to the invention;

FIG. 14 is a schematic view in cross section of the tubular member of FIG. 13,

FIG. 15 is a schematic sectional view along line B-B of the distribution device of FIG. 13,

FIG. 16 is a diagrammatic view in cross section of a tubular planet carrier member,

FIGS. 17 and 18 are schematic sectional views along lines A-A and B-B of FIG. 16,

- Figure 19 is a schematic view in axial section of a tubular planet carrier, equipped with another alternative embodiment of the device according to the invention;

FIG. 20 is a schematic sectional view along line A-A in FIG. 19,

- Figure 21 is a schematic view in axial section of a tubular planet carrier, equipped with another alternative embodiment of the device according to the invention;

FIG. 22 is a schematic sectional view along line A-A in FIG. 21, and

- Figure 23 is a schematic perspective view of another alternative embodiment of a device according to the invention.

Detailed description of an embodiment of the invention

FIG. 1 shows a turbomachine 1 which conventionally comprises a fan propeller S, a low pressure compressor 1a, a high pressure compressor 1b, an annular combustion chamber 1c, a high pressure turbine 1d, a low pressure turbine 1e and an exhaust nozzle 1h. The high pressure compressor 1b and the high pressure turbine 1d are connected by a high pressure shaft 2 and form with it a high pressure body (HP). The low pressure compressor 1a and the low pressure turbine 1e are connected by a low pressure shaft 3 and form with it a low pressure body (BP).

The fan propeller S is driven by a fan shaft 4 which is coupled to the LP shaft 3 by means of an epicyclic reduction gear 10 shown here diagrammatically.

The reduction gear 10 is positioned in the front part of the turbomachine. A fixed structure schematically comprising, here, an upstream part 5a and a downstream part 5b is arranged so as to form an enclosure E1 surrounding the reducer 10. This enclosure E1 is here closed upstream by seals at a level allowing the crossing of the fan shaft 4, and downstream by seals at the crossing of the LP shaft 3.

With reference to FIG. 2, the reduction gear 10 essentially comprises a so-called solar planetary gear pinion 11 whose axis of rotation is centered on the axis X of the turbomachine, a ring 14 extending around the sun and whose axis of revolution is centered on the X axis, and a series of pinions of satellites or satellites 12 which are arranged between the sun 11 and the ring 14 and meshed with them. The number of satellites 12 is generally defined between three and five, up to seven.

With reference to FIG. 3, the crown 14 is fixed and fixed by means of flanges 20 to the fixed structure 5a, 5b of FIG. 1. The reduction gear 10 engages on the one hand on the shaft BP 3 by the intermediate of grooves 7 which drive the solar 11, and on the other hand on the fan shaft 4 which is attached to a planet carrier 13. Each satellite 12 rotates freely around an axis Y defined by a tubular support 16 carried by the planet carrier 13, using a bearing 17.

The rotation of the satellites 12 around their axis Y, due to the cooperation of their teeth with the teeth of the crown 14, causes the rotation of the planet carrier 13 around the axis X, and consequently that of the shaft fan 4 which is linked to it, at a speed of rotation which is lower than that of the BP shaft 3.

Figures 3 and 4 show the routing of the oil to the reducer 10 and its path inside it. Arrows show in FIG. 3 the path followed by the oil from, in this example, an adapter part 31 linked to the fixed structure of the turbomachine, up to the pinions and the bearings 17 to be lubricated.

The lubrication means schematically comprise three parts which will be described below successively, a first part linked to the fixed structure and delivering the oil to the rotating parts of the reduction gear 10, a impeller (or centrifugal scoop 35) rotating with the holder -satellites 13 receiving this oil, and oil distribution circuits supplied with oil by the impeller to route it to the places to be lubricated. The first part comprises at least one injector 32, the calibrated end of which is tightened to form a nozzle 33. The oil is brought to the injector by a conveying pipe 30, coming from the engine tank (not shown). The adapter piece 31 can be interposed next to the reducer 10 on the pipe, preferably in the upper part so that the oil can flow towards the center of the reducer by gravity. The nozzle 33 ejects the oil in the form of a jet 34. The nozzle 33 is positioned here radially inside the planet carrier 13 and the scoop 35 relative to the axis X and the jet 34 is oriented with a radial component directed towards the outside of the reduction gear 10 so as to impact the bottom of the scoop 35. With reference to FIG. 4, the oil receiving wheel linked to the planet carrier 13 essentially comprises a scoop centrifugal 35, here in U-shaped section, whose U-shaped opening is oriented towards the axis of rotation X. The impeller is arranged on the satellite carriers 13 so that the bottom of the U of the scoop 35 collects the oil jet 34 ejected by the nozzle 33.

A first series of oil distribution circuits corresponds to first pipes 43, which are distributed regularly over the circumference of the reduction gear 10 and in a number equal to that of the satellites 12. These pipes 43 start radially from the scoop 35 and penetrate into the internal chamber 16a of each support 16 (FIG. 3), which is closed by the planet carrier 13. The oil which circulates in the first pipes 43 enters the internal chamber 16a then passes, due to the centrifugal force, into passages 44, which pass through each support 16 while being oriented radially. These passages 44 open at the periphery of the supports 16, at the level of the bearings supporting the pinions of the satellites 12 and thus ensure the lubrication of these bearings. The second series of oil distribution circuits includes second lines 45 which pass from the scoop 35 between the satellites 12 and are divided into several channels 45a, 45b. The channels 45a, 45b convey the oil to the gears formed by the pinions of the satellites 12 and the sun 11, on the one hand, and the pinions of the satellites 12 and the outer ring 14, on the other hand. Each channel 45a extends axially along the pinions of a satellite 12, between these and the sun 11, and forms a lubrication ramp over the entire width of the pinions. The channel 45b, which feeds the gear between the crown 14 and the pinions of the satellites 12, projects its oil into the center of the cylinder formed by each satellite 12. As shown, each satellite 12 is produced in the form of two parallel pinions which mesh respectively with two half-crowns of the crown 14 (Figure 3). The propellers of the teeth of each satellite are oriented diagonally to the axis Y of rotation of the satellite 12, so as to give them a function of grooves in which the oil is entrained, from the middle of the cylinder to its periphery, to lubricate the gear over its entire width.

FIGS. 5 and 6 very schematically show one of the tubular supports 16 of the planet carrier 13. This support 16 comprises an internal cylindrical surface 16b defining the abovementioned internal chamber 16a, and an external cylindrical surface 16c on which an internal ring is mounted 50 of a bearing 17 here with bearings and more exactly with rollers.

The combination of a tubular support 16 and an inner ring 50 of a rolling bearing forms, in the context of the present invention, a tubular member of a planet carrier. As is the case with the supports 16 and the rings 50, the tubular members are preferably distributed regularly around the sun gear of the reduction gear.

The internal ring 50 includes an internal cylindrical surface 50a which is supported on the surface 16c and external cylindrical surfaces 50c between which are arranged external cylindrical guide tracks 50b. The tracks 50b are two in number and make it possible to guide two adjacent annular series of rollers 52. The surfaces 50c are three in number and make it possible to guide cages 54 for holding the rollers of the two series. Each track 50b is located between two surfaces 50c.

The oil which is brought into the chamber 16a of each tubular support 16 is conveyed to the bearing 17 by the aforementioned passages 44 (FIG. 3) which on the one hand comprise holes 56 formed in the support 16 and conduits 58 formed in the inner ring 50. The holes 56 have a substantially radial orientation and extend in the thickness of the support 16 from the surface 16b to circumferential grooves 60 formed on the surface 16c. The conduits 58 also have a substantially radial orientation and extend in the thickness of the inner ring 50, from the surface 50a to the tracks 50b and surfaces 50c. Some conduits 58 open onto the tracks 50b for the lubrication of the rollers 52 and others open onto the surfaces 50c for the lubrication of the cages 54.

In the case shown in Figures 5 and 6, the grooves 60 have a circumferential orientation and extend around the axis Y of revolution of the support 16, over about 300 °. The reference 62 designates the oil supply point for the chamber 16a and therefore for the injection of oil through the aforementioned pipe 43 (FIGS. 3-4).

As mentioned in the foregoing, the planet carrier 13 is movable in rotation around the axis X (shown in FIG. 5) and the supply of oil to each support 16 is carried out at a point 62 distant from this axis. The oil is centrifuged as soon as it is supplied from chamber 16a. The centrifugal fields applied to the oil are all the more important as this oil is distant from the X axis. The arrows F1 and F2 represent the influence of these fields on the oil pressure. The further one moves away from the axis from point 62, the more the pressure increases due to the centrifugal fields, and the closer one gets to the axis and the more this pressure decreases due to the centrifugal fields. The oil flow is thus the highest on the passages furthest from the center of rotation and the lowest on the closest passages, precisely where the need for lubrication is greatest (the cages 54 of the bearing 17 exerting significant pressure on the tracks of the inner ring 50).

These problems of differences in flow rate can lead to significant friction and to the removal of material from the surfaces 50c of the ring 50.

The description which follows with reference to FIGS. 7 et seq. Explains the various aspects of the invention which allow optimization of the lubrication of a gearbox with rotating planet carrier for which the lubricating oil is subjected in operation to centrifugal fields. important.

Figure 7 illustrates two aspects of the invention.

The first aspect relates to the integration of a device 64 for distributing oil in each tubular support 16 of a planet carrier of the reducer.

The device 64 comprises a disc configured to be coaxially integral with a tubular support and comprising at least two internal cavities 66 connected in series by one or more calibrated orifices 68, one of these cavities, called the receiving cavity 66a, being connected to the oil inlet 62, and calibrated internal oil delivery channels 70 extending from the cavities 66 to the oil outlet orifices 70a provided at the external periphery of the disc.

The device 64 or the disc can be directly integrated and therefore formed in one piece with the tubular support 16. As a variant, it is attached and fixed, for example by shrinking, in the tubular support.

As in the example shown, the cavities 66 are preferably arranged along a line Z which passes substantially through the center of the disc. This line Z can be oriented in a radial direction relative to the axis X of rotation of the planet carrier.

The cavities 66 are here five in number and are separated from each other by diaphragms comprising the aforesaid calibrated orifices 68. The holes 68 are aligned on the line Z in the example shown. The oil inlet 62 is here connected to the cavity closest to the X axis and the periphery of the disc.

The number of channels 70 can be a function of the number of cavities 66 and the number of grooves 72 which are formed on the external cylindrical surface 16c of the support and which must be supplied with oil. Each groove 72 is fed by a single channel 70 in the example shown and is connected to this channel by a single hole 56 in the support 16. The channels 70 and the cavities 66 preferably extend in the plane of the disc. They are formed for example in the thickness of this disc.

Each cavity 66 is here connected to at least two channels 70. The cavity 66a connected to the oil inlet 62, which is located closest to the axis X, is connected by three channels 70 with three grooves 72. L one of these three channels 70 extends from the cavity 66a towards the axis X, along the line Z, and the other two extend on either side of the cavity 66a. The other cavities 66 are connected by two channels 70 to two grooves 72, the two channels of each cavity being located on either side of this cavity. The channels extend substantially radially from the Y axis of the support radially outward and the device has symmetry with respect to a plane passing through the line Z and perpendicular to the plane of the disc.

The holes 56 of the support extend here in the extension of the channels 70 of the device and of their oil outlet orifices 70a.

According to the invention, the grooves 72 have an axial orientation and not a circumferential one, that is to say that they extend along the axis Y. The number of grooves 72 can vary and depends in particular on the number angular sectors of the tracks 50b and surfaces 50c to be lubricated, independently of each other. In the example shown, this number is eleven.

The grooves 72 preferably have a circumferential width or dimension around the axis Y which is greater than the diameter of the channels 70, the holes 56 as well as the conduits 58. As can be seen in FIG. 7, each groove 72 comprises two edges longitudinal 72a, 72b opposite, a first 72a is located closest to the X axis (relative to the second) and is connected to conduits 58, and the second 72b is located farthest from this axis X (relative to the first) and is connected to hole 56.

This misalignment Δ between the conduits 58, on the one hand, and the channel 70 and the hole 56, on the other hand, relates to the second aspect of the invention and makes it possible to ensure an equitable distribution of the oil in all the holes 56 located on the same angular sector, from upstream to downstream of the internal ring 50, despite the oil supply by a single channel 70 and a single hole 56. Indeed, in operation, the oil is routed through the corresponding channel 70 in the groove 72, at its longitudinal edge 72b, the oil then reaches the conduits 58 which are connected to the opposite edge 72a and are preferably all located in the same axial plane for a given sector of the ring 50.

In order to balance the flow rates in the different holes 56, the diameters of the calibrated orifices 68 of the diaphragms and the sections of the channels 70 can be adjusted. These must decrease as they move away from the axis X, in a proportion to be defined using a hydraulic model. The channels 70 which extend from a cavity 66, substantially towards the axis X, as is the case of the channels connected to the cavity 66a connected to the oil inlet 62, therefore have a passage section which can increase towards the X axis. The channels 70 which extend from a cavity 66, substantially opposite the X axis, therefore have a passage section which can decrease towards the X axis. Finally, the channels which are generally at the same distance from the X axis, over their entire extent, could have an identical passage section. The diameters of the calibrated orifices 68 decrease as they move away from the X axis. The diameters of the channels 70 can vary between 0.5 and 3mm, and preferably between 0.7 and 2mm. The diameters of the calibrated orifices 68 can vary between 0.5 and 7mm, and preferably between 0.7 and 5mm.

Thanks to the symmetry of the device 64, the channels 70 located on either side of each cavity 66 receive the same flow rate, which is impossible to obtain with circumferential grooves as illustrated in FIGS. 5 and 6.

Given the high pressure exerted by the cages 54 which are centrifuged against the support 16, the conduits 58 of the internal ring 50 opening onto the surfaces 50c of the cages (those closest to the center of rotation, encircled in FIG. 7) must allow the formation of an oil wedge for hydrodynamic operation. The formation of this wedge of oil can be facilitated by creating bowls 74 (FIG. 8) on the tracks, into which the conduits 58 open.

Figures 9 to 12 illustrate a first embodiment of an oil distribution device 64 according to the invention.

The device 64, still in the form of a disc, here comprises two parts, namely a base 76 and a cover 78, both annular and intended to be fixed coaxially to one another.

As described in the foregoing, the device 64 is here intended to be engaged in the tubular support 16 and to be fixed there by shrinking. The base 76 and the cover 78 preferably have the same external diameter and are both intended to be shrunk in the tubular support 16, or in the support 16 and the ring 50, as shown in FIG. 9. Annular seals of sealing 82 can be mounted between the device and the support 16 and / or the ring 50 to prevent any oil leakage during operation.

The base 76 comprises two parallel flat faces, one of which is machined to define therein the locations and the volumes and dimensions of the cavities

66, orifices 68 and channels 70. The cover 78 is attached to the base 76 to close these volumes. The channels 70 extend here from the cavities 66 to outside rectilinear lunules 80, which are parallel to each other and to the axis Y of the device, and are intended to be connected to the holes 56 or to the grooves 72 mentioned above. .

The machining of the base 76 is for example carried out using a single ball milling cutter. The hydraulic diameter of each portion would then be adjusted, for example by varying the depth of penetration of the cutter. FIG. 9 shows for example that the machining depth of the cavities 66 is greater than that of the channels 70 and orifices 68. The bearing faces of the base 76 and of the cover 78 must be perfectly flat and rectified to ensure good seal. The hooping of the device 64 must make it possible to avoid the passage of oil between the lunulas 80.

The cavity 66a which is located closest to the periphery of the device is here that which is located closest to the axis X and which is connected to the oil inlet 62. This cavity opens radially on the external periphery of the base 76 so that a hole 56 of the support 16 can be directly in fluid communication with this cavity (without intermediate channel - Figure 9).

FIG. 11 represents a tubular support 16 and the internal ring 50 mounted on this support, and illustrates the second aspect of the invention described in the foregoing. Each groove 72 is connected, on the one hand, to several conduits 58 situated in planes perpendicular to the different axis Y, and, on the other hand, to a single hole 56. The holes 56 of the support do not appear here because the section shown does not pass through these holes. This section passes through one of the conduits 58 for each groove 72.

Figure 12 shows a similar view with the device of Figures 9 and 10, which is mounted coaxially with the support. As can be seen in this figure, the lunulas 80 are aligned opposite the grooves 72, and in particular the longitudinal edges 72b of these grooves, the most distant from the axis X.

Figures 13 to 15 illustrate a second embodiment of an oil distribution device according to the invention.

Like the previous embodiment, the device 64, still in the form of a disc, here comprises two parts, namely a base 76 and a cover 78, both annular and intended to be fixed coaxially to each other.

The device 64 is here intended to be engaged in the tubular support 16 and to be fixed there by shrinking (FIG. 13). The base 76 and the cover 78 preferably have the same external diameter and are both intended to be shrunk into the tubular support.

The base 76 comprises two parallel flat faces, one of which is machined to define therein the locations and the volumes and dimensions of the cavities 66, the orifices 68 and the channels 70. The cover 78 is attached to the base to close these volumes. The assembly is fixed by bolts 83 which pass through holes 84 aligned with the base and the cover (FIGS. 14 and 15). A brake wire can be used to connect the bolts 83 together and thus prevent their accidental loosening.

The machining of the base 76 is for example carried out using a single ball milling cutter. The hydraulic diameter of each portion would then be adjusted, for example by varying the depth of penetration of the cutter. FIG. 9 shows, for example, that the depth of machining of the cavities 66 is greater than that of the channels 70 and orifices 68. The bearing faces of the base and of the cover must be perfectly flat and rectified to ensure good sealing.

The cavity 66 which is located closest to the periphery of the device is here that which is located closest to the axis X and which is connected to the oil inlet 62. This cavity is connected by an aligned channel 70 on the line Z at the corresponding hole 56 of the support 16. This cavity also opens axially inside the chamber 16a of the support 16 so as to be connected to the oil inlet 62.

The cavities here have a generally cylindrical shape whose axis is oriented perpendicular to the plane of the disc forming the device.

In the example shown, the base 76 is integral with a gripping member 84 to facilitate assembly and disassembly of the device and in particular its shrinking. The device 64 further comprises an indexing means for its angular positioning in the tubular support 16. It may be an orifice 86 passing through the base and the cover and positioned in a predetermined location, for example diametrically at the opposite the oil inlet 62. During assembly, an operator is intended to angularly position the device in the support by means of an indexing pin 88 which is intended to be engaged in the orifice 86.

Advantageously, the length of the pin 88 intended to be engaged in the orifice 86 is greater than the length L of the hooping zone of the device in the support 16, so that the engagement of the pin in the lunula of the shoulder 90 and therefore the angular positioning of the device take place before the effective hooping of the device in the support. Tightening would make it difficult to position the posterior angularly.

The device 64 is preferably in axial support on an internal cylindrical shoulder 90 of the support in the hooped position. In addition to the shrinking, the oil pressure being exerted on the upstream face of the device, the latter is not likely to deviate from the shoulder 90 against which it abuts.

FIGS. 16 and 17 make it possible to view the number and the position of the conduits 58 for lubricating the tracks 50b, which are connected to one of the longitudinal edges 72a of a groove 72. As mentioned in the foregoing in relation to the second aspect of the invention, the hole 56 is connected to the opposite longitudinal edge 72b of this groove, but its axial position with respect to this groove does not matter. The same applies to each hole 56 for feeding an oil delivery groove to the lubrication conduits of the surfaces 50c (Figures 16 and 18).

Figures 18 and 19, on the one hand, and 20 and 21, on the other hand, illustrate two other exemplary embodiments of an oil distribution device according to the invention.

These two variants use a device in the form of a disc as shown in FIG. 22. The disc comprises in its plane an internal bore 92 which is stepped along the line Z and which comprises a series of sections of different diameters and arranged increasing or decreasing in the direction considered along the line Z. The bore is for example achieved by means of a drill or several drills with flat end (s). Pellets 94 pre-drilled are engaged and fixed, preferably by shrinking, in the sections of the bore 92 and are intended to define between them the aforementioned cavities 66 of the disc. The pellets 94 are pre-drilled to define the calibrated orifices 68 and therefore form the diaphragms mentioned in the foregoing. The larger diameter cavity is intended to be connected to the oil inlet 62 and opens at the periphery of the disc. The bore 92 is produced by machining the disc, starting with this larger diameter cavity. The number of sections of the bore corresponds to the number of cavities in the disc.

In the alternative embodiment of Figures 19 and 20, the device 64 does not have symmetry as mentioned in the foregoing. The cavities 66 are well aligned along a line Z but which is not oriented in a radial direction relative to the axis X of rotation of the planet carrier but it is slightly offset to favor the appearance of a wedge of oil. The channels are not necessarily regularly distributed around the axis Y of the support 16. The device here comprises only four cavities 66 and six channels 70. Five channels 70 supply holes 56 for supplying oil to the tracks 50b for guiding the rollers, and a channel 70 feeds the oil supply hole to the guide track of the cage or cages. The arrow F3 illustrates the direction of rotation of the cage.

In the alternative embodiment of Figures 21 and 22, the device 64 does not have symmetry as mentioned in the foregoing. The cavities 66 are well aligned along a line Z. The line Z is not oriented in a radial direction relative to the axis X of rotation of the planet carrier but it is slightly offset to favor the appearance a corner of oil. The channels are not necessarily regularly distributed around the axis Y of the support 16. The device here comprises only four cavities 66 and five channels 70. All these channels 70 supply holes 56 for supplying oil to the guide tracks 50b rollers. These holes are all located in the same plane perpendicular to the Y axis. The oil supply to the cage guide track is provided by a simple hole 71.

Figures 19 and 21 also show a tubular support 16 of a planet carrier. It can be seen that this support comprises a transverse wall 96 in the thickness of which the device according to the invention could be formed which could thus be integrated into the support.

Claims (10)

1. Rotating planet carrier (13) for a mechanical reduction gear (10) of a turbomachine, this planet carrier comprising an annular row of tubular members (16, 50) for bearing supports (17) which are parallel to each other and to an axis of rotation (X) of the planet carrier, each of said tubular members comprising an external peripheral surface defining tracks and cylindrical surfaces (50b, 50c) for guiding bearings and at least one cage of these bearings, and an internal cylindrical surface (16b) delimiting an internal chamber (16a) configured to be supplied with oil in operation, oil passages (56, 58) extending between the internal cylindrical surface and the external peripheral surface for routing oil from said chamber to the bearings and the cage, characterized in that each of the tubular members comprises grooves (72) for circulation of oil which are connected to conduits (58) forman t at least part of said passages and extending from the grooves to said external peripheral surface, these grooves being substantially rectilinear and parallel to each other as well as to an axis of revolution (Y) of said internal cylindrical surface of the corresponding tubular member, at least some of said grooves having an angular width or extent around said axis of revolution, which is greater than the diameter of the conduits connected to this groove, and at least some of said conduits being connected to the corresponding groove at the level of the one of the longitudinal edges (72a) of this groove, namely that which is closest to said axis of rotation (X) of the planet carrier. 2. planet carrier (13) according to the preceding claim, wherein each of said tubular members comprises a tubular support (16) and an inner ring (50) of at least one rolling bearing (17), this inner ring being integrated to said support or attached and fixed around said support. 3. planet carrier (13) according to the preceding claim, wherein each of said tubular supports (16) comprises an external cylindrical surface (16b) on which is mounted said internal ring (50), said passages comprising, on the one hand, said conduits (58) which extend between said external peripheral surface defined by the ring and said grooves (72), and, on the other hand, through holes (56) which extend between said internal cylindrical surface and said grooves , the grooves being formed between the tubular support and the ring. 4. planet carrier (13) according to the preceding claim, wherein said grooves (72) are formed on the outer cylindrical surface (16b) of each tubular support (16). 5. planet carrier (13) according to claim 3 or 4, wherein said holes (56) are connected to the grooves (72) at the other of the longitudinal edges (72b) of these grooves, namely that which is the farthest from said axis of rotation (X) of the planet carrier. 6. planet carrier (13) according to the preceding claim, wherein each of said grooves (72) is connected to several conduits (58), on the one hand, and to a single hole (56), on the other hand. 7. planet carrier (13) according to one of the preceding claims, in which an oil distribution device (64) is associated with each of said tubular members (16, 50), this device being configured to be coaxially integral with the corresponding tubular member. 8. planet carrier (13) according to the preceding claim, wherein said device comprises an oil inlet (62) and a row of oil outlets opening onto an external surface intended to be surrounded at least in part by the member, said device comprising at least two internal cavities (66) connected in series by at least one orifice (68) calibrated, one of these cavities, called receiving cavity (66a) being connected to said oil inlet, and channels internal (70) calibrated oil delivery extending substantially radially from said cavities to orifices in said external surface of the device to form said oil outlets which are in fluid communication with said grooves (72). 9. planet carrier (13) according to claim 7 or 8, wherein said device is configured to be attached and fixed, for example by shrinking, 5 in said tubular member (16, 50). 10. Aircraft turbomachine, characterized in that it comprises a planet carrier (13) according to one of the preceding claims.